Roof-Friendly Solar

Certain­teed’s polycrystalline Apollo Solar Roofing uses solar cells protected by a layer of plastic rather than glass, making it lighter than many other products. The panels integrate with the roof shingles, so they should be less stressed by wind uplift than rack-mounted systems. At $6 per watt, a 4-kw system costs about $24,000, but tax credits and utility incentives could reduce that considerably.